Can't charge my iphone in my car.. ARGH!

I have bought two USB-car chargers so far to charge my iphone in my car but none of them works!!!

First one was looks like this,

I bought a belkin iphone accessory pack, and it came with it.
When I use this charger, my iphone would say it's charging- battery icon popping up. But then about 30seconds later it would turn on the light on by itself indicating that it has been disconnected. 30 seconds later, it's charging.. repeat..

The accessory pack was really cheap and I thought I have received a faulty one..

So I bought this last night!

I plugged my iPhone cable to the USB slot and nothing happens...
Nothing at all. No response from the iphone.

When I inserted my old charger to one of the three slots, it had the same result as just plugging it in to the ciggarate slot directly.. So maybe the USB slot is just faulty??

I can't believe I have to buy a third charger to plug it into the second charger I bought..

Try paying attention to the specs. 500mA can charge if you're not using much power while it's charging. Even so it will be very slow. Aim for ~1A/1000mA. This is mentioned in many of the former threads on charging.

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